The management and exchange of multimedia data is a hallenging area of research due to variety of formats, standards, and the many interesting planned applications. Semantic Web technologies are very promising to enable interoperability and integration of media. Many research groups are active in finding and proposing interesting solution or standards. Within MUSCLE, research is focusing on standards, technologies and techniques for integrating, exchanging and enhancing the use of multimedia within a variety of research areas. At ISTI-CNR, we studied and developed a prototype of infrastructure for MultiMedia Metadata Management (named 4M) that should support the integration of media from different sources. This infrastructure enables collection, analysis and integration of media for semantic annotation, search and retrieval. In order to design a modern and adequate system, we took into account the use of (i) Semantic Web technology, (ii) multimedia metadata standards, (iii) existing tools, and (iv) open-source software. In particular, we chose an open-source native-XML database (eXist) to implement the metadata management unit. During this work, many troubles were found in the actual available release of the database. As a consequence, we developed new operations that have been added at the libraries contained in the exist.jar file (java archive). These extensions have been submitted to the eXist developers and are now in a testing phase before their final insertion into a new correct release (https://sourceforge.net/tracker/?func=detail&atid=317691&aid=1597055&group_id=17691 ).